#include <iostream>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;
#define eps 1e-8
#define zero(x) (((x) > 0 ? (x) : -(x)) < eps)
int o[200];
struct point
{
    double x, y;
} p[1001];
double dis(point p1, point p2)
{
    return (p1.x - p2.x) * (p1.x - p2.x) + (p1.y - p2.y) * (p1.y - p2.y);
}
int judge(int i, int j, int k)
{
    if (zero(dis(p[i], p[j]) - dis(p[j], p[k])) && zero(dis(p[i], p[j]) - dis(p[i], p[k])))
        return 1;
    else
        return 0;
}
char str[1001];
int main()
{
    int n, i, j, k, num = 1, len, flag;
    double d;
    p[0].x = 0;
    p[0].y = 0;
    for (i = 2; i <= 12; i++)
    {
        d = (i - 1) * 1.0 * sqrt(3.0) * 2.0 / 3.0 / (i - 1);
        p[num].x = -(i - 1) * 1.0 * sqrt(3.0) / 3.0;
        p[num].y = i - 1;
        num++;
        for (j = 1; j < i; j++)
        {
            p[num].x = p[num - 1].x + d;
            p[num].y = i - 1;
            num++;
        }
    }
    while (scanf("%d", &n) != EOF)
    {
        if (n == 0)
            break;
        memset(o, 0, sizeof(o));
        scanf("%s", str);
        len = strlen(str);
        flag = 0;
        for (i = 0; i < len; i++)
        {
            for (j = i + 1; j < len; j++)
            {
                if (str[i] == str[j])
                    for (k = j + 1; k < len; k++)
                    {
                        if (str[j] == str[k])
                        {
                            if (judge(i, j, k))
                            {
                                flag = 1;
                                o[str[i] + 0]++;
                            }
                        }
                    }
            }
        }
        if (!flag)
        {
            printf("LOOOOOOOOSER!\n");
            continue;
        }
        for (i = 0; i <= 128; i++)
        {
            if (o[i])
            {
                for (j = 1; j <= o[i]; j++)
                    printf("%c", i);
            }
        }
        printf("\n");
    }
    return 0;
}